4.2.1 The Quest project (Canada)

In this section the monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions plans for the Shell Quest project in Canada are analysed and discussed in terms of legislation. All information is based on documentation made publicly available through the website of Shell, including the appendix A of the project description documents describing the MMV plan (Shell, 2010).

The Quest project in Canada encompasses an integrated, full CCSCarbon dioxide Capture and Storage chain, related to the exploitation of oil sands. Quest will captureThe separation of carbon dioxide from other gases before it is emitted to the atmosphere more than one million tonnes of CO2Carbon dioxide per year from Shell's Scotford Upgrader, located near Fort Saskatchewan, Alberta. It is planned to transport CO2Carbon dioxide via a pipeline of about 80 km length in order to store in a highly saline sandstoneSand that has turned into a rock due to geological processes aquiferAn underground layer of fluid-bearing permeable rock or unconsolidated materials (gravel, sand, or silt) with significant permeability to allow flow of Cambrian age at a depth of about 2 km.

The starting point for the development of the monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions (or MMV) plans has been the CO2QUALSTORE documents by DNV (2010a), where practical guidelines and examples are provided on how to develop this. The approach followed is riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event based. The Bowtie Method (DNV 2010a) is used as an appropriate framework for a systematic risk assessmentA process intended to calculate or estimate the risk to a given target, part of a risk management system of events with the potential to affect storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere performance. The monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions plan includes multiple independent monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions systems with the required sensitivity, response time, and scale to generate reliable early warnings of any potential loss of containmentRestriction of the movement of a fluid to a designated volume (e.g. reservoir). It is linked to risks and to modelling in the following aspects:

1. Loss of conformance; where conformance means the behaviour inside the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere complex is consistent with model-based predictions. Therefore, lack of conformance is a project riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event relating to the long-term liability (and to the site closure) and not a HSSE-critical riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event - a high-level riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event analysis is sufficient for the monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions plan
2. Loss of containmentRestriction of the movement of a fluid to a designated volume (e.g. reservoir); this is a HSSE-critical riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event, so a detailed and comprehensive approach to the bow-tie analysis is required. These are possible impacts on groundwater and hydrocarbon resources, soil contamination, CO2Carbon dioxide leaks into atmosphereThe layer of gases surrounding the earth; the gases are mainly nitrogen (78%) and oxygen (around 21%), corrosion of legacy wells, CO2Carbon dioxide migrationThe movement of fluids in reservoir rocks along an injectionThe process of using pressure to force fluids down wells wellManmade hole drilled into the earth to produce liquids or gases, or to allow the injection of fluids, caprockRock of very low permeability that acts as an upper seal to prevent fluid flow out of a reservoir integrity. The monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions targets include measurements of any changes within the hydrosphere, biosphere, and atmosphereThe layer of gases surrounding the earth; the gases are mainly nitrogen (78%) and oxygen (around 21%) caused by CO2Carbon dioxide injected into the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere complex are sufficient to demonstrate the absence of any significant environmental impacts on an annual basis.

In both cases, two distinct types of preventative and corrective safeguards have been defined:

1. Passive safeguards: These safeguards are always present from the start of injectionThe process of using pressure to force fluids down wells and do not need to be activated at the appropriate moment. These passive safeguards exist in two forms:

2. 1. Geological barriers identified during site characterisation;

   2. Engineered barriers identified during engineering concept selections.

3. Active safeguards: These are engineered safeguards, brought into service in response to some indication of a potential upset condition in order to make the site safe. Each active safeguard requires three key components in order to operate effectively:

4. 1. A sensor capable of detecting changes with sufficient sensitivity and reliability to provide an early indication that some form of intervention is required;

   2. Some decision logic to interpret the sensor data and select the most appropriate form of intervention;

   3. A control response capable of effective intervention to ensure continuing storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere performance or to control the effects of any potential loss of storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere performance.

From the risk assessmentA process intended to calculate or estimate the risk to a given target, part of a risk management system it can probably be concluded, that the major uncertainties for integrity of the reservoirA subsurface body of rock with sufficient porosity and permeability to store and transmit fluids are related to the (abandoned) wells penetrating the reservoirA subsurface body of rock with sufficient porosity and permeability to store and transmit fluids rock. Not only in terms of CO2Carbon dioxide leakage(in CO2 storage) The escape of injected fluid from the storage formation to the atmosphere or water column, but possibly for brine migrationThe movement of fluids in reservoir rocks out of the reservoirA subsurface body of rock with sufficient porosity and permeability to store and transmit fluids rock along these wellbores. This has been taken into account in the selection of the injectionThe process of using pressure to force fluids down wells area, where the distance to existing wells has been maximized. Currently the closest wellManmade hole drilled into the earth to produce liquids or gases, or to allow the injection of fluids is at a distance of 21 km, and the closest updipInclining upwards following a structural contour of strata wellManmade hole drilled into the earth to produce liquids or gases, or to allow the injection of fluids at 31 km.

This riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event factor has a strong influence on the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere complex and the extent of the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere Area Of Interest (AOI), that is guided by the expected extent of the pressure front after 25 years of injectionThe process of using pressure to force fluids down wells at an average rate of about 1 MtMillion tonnes per year. The AOI is not the same as the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere complex, but is a larger area that needs to be monitored. The safety margin and pressure monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions threshold value ensuring safe operations is based on scenarioA plausible description of the future based on an internally consistent set of assumptions about key relationships and driving forces; note that scenarios are neither predictions nor forecasts modelling of different subsurface models, that predict the start of brine migrationThe movement of fluids in reservoir rocks upwards through the legacy wells far away (20 km) as a function of the anticipated pressure rises. As raised earlier in the section comparing the IEAInternational Energy Agency-MRF and the EU CCS DirectiveDirective 2009/31/EC of the European Parliament and of the Council of 23 April 2009 on the geological storage of carbon dioxide, the EU CCS DirectiveDirective 2009/31/EC of the European Parliament and of the Council of 23 April 2009 on the geological storage of carbon dioxide is much less prescriptive about how to deal with the pressure increase. It does show once more, that pressure monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions is the key technology to ensure safe storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere.

This example also shows the importance of taking uncertainty into account for modelling. An important statement was made in the documents by Shell, stating that the models should represent the entire uncertainty range, but need to provide sufficient confidence at the same time to carry on the operations. Again an issue, that is addressed in the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere directive as wellManmade hole drilled into the earth to produce liquids or gases, or to allow the injection of fluids, but in a "soft" manner. The expectation is of course, that uncertainties will diminish as more monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions data comes in during operations.

In the documented monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions plans, at least three deep monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions wells are to be drilled where continuous pressure measurements will be carried out. For each injectionThe process of using pressure to force fluids down wells wellManmade hole drilled into the earth to produce liquids or gases, or to allow the injection of fluids three groundwater monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions wells will be drilled (in order to conduct electrical conductivity measurements and annual fluid sampling and analyses), at least one of them close to the injectionThe process of using pressure to force fluids down wells wellManmade hole drilled into the earth to produce liquids or gases, or to allow the injection of fluids. Geochemical signatures of brine from the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere site (Cambrian saline aquiferAn underground layer of fluid-bearing permeable rock or unconsolidated materials (gravel, sand, or silt) with significant permeability to allow flow) have been identified and are to be used in order to detect a possible brine leakage(in CO2 storage) The escape of injected fluid from the storage formation to the atmosphere or water column into groundwater during fluid sampling and analyses. In all injectionThe process of using pressure to force fluids down wells wells a distributed temperature sensing system will be installed.

In general the monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions encompasses in-wellManmade hole drilled into the earth to produce liquids or gases, or to allow the injection of fluids monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions to ensure integrity of the wellManmade hole drilled into the earth to produce liquids or gases, or to allow the injection of fluids and to monitor downhole parameters like pressure, geochemical monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions at various levels from shallow and deep wells, geophysical methods to monitor the CO2Carbon dioxide extent and possibly pressure increases, and near surface monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions.

As an early warning system for leakage(in CO2 storage) The escape of injected fluid from the storage formation to the atmosphere or water column, both geophysical and in-wellManmade hole drilled into the earth to produce liquids or gases, or to allow the injection of fluids techniques are used. In the Quest project monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions from wells in the aquiferAn underground layer of fluid-bearing permeable rock or unconsolidated materials (gravel, sand, or silt) with significant permeability to allow flow above the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere reservoirA subsurface body of rock with sufficient porosity and permeability to store and transmit fluids is also envisaged to detect anomalies in chemical composition of pressure increases.

Concerning geophysics, a baseline 3D surface seismic survey is planned. 3D VSP surveys are to monitor the CO2 plumeDispersing volume of CO2-rich phase contained in target formation extent at the early stage of injectionThe process of using pressure to force fluids down wells. Once the plume spreading becomes too extensive to be covered by the VSP measurements, a repeat 3D surface seismic survey will take over.

Other techniques operating at the surface include InSAR data designed to monitor surface heave induced by CO2Carbon dioxide storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere and remote sensing data designed to detect environmental change (e.g. multi-spectral image analysis) are to be acquired. Also the line of sight CO2Carbon dioxide gas flux monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions will be applied.

More details on the monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions approach including a full list of techniques can be found in the documentation on the website.